<!DOCTYPE html>
<html>
<body>
    <h1>JavaScript 函数</h1>
    <p>函数存储在变量后，变量可以用作函数：</p>
    <p id="demo"></p>
    <script>
        var x = function (a, b) {
            return a * b
        };
        document.getElementById("demo").innerHTML = x(4, 3);
    </script>
</body>
</html>